Error 401 [Please Help]

Currently trying to beat Sarven Treasure 3 (The reapeatable level that gets harder as you go).
Everytime I try to do it I get this error : https://gyazo.com/75c69738c39ef02cd2a1e53d50ff5c42
It’s not the type of error you get when your code is wrong, but a different type of error that I’ve never gotten until now. Could anybody help? @nick @Bryukh

You think its a bug?